Veteran animation artist Floyd Norman has written a great piece for Jim Hill Media about what it was like to work in the Disney “bullpen” during the 1950s. The bullpen is described by Floyd as:
…the animation equivalent of the secretarial pool in the modern office environment. It was a training ground for the young artists as well as a resource for the animators needing their scenes in-betweened. Every young artist dreamed of moving out of the “Bullpen” and occupying a seat next to a real Disney animator.
For another vintage look at the Disney bullpen, see this post at the Animation Guild Blog with a 1954 caricature by John Sparey of Disney bullpenners.